Abstract
Background
Cardiac allograft vasculopathy (CAV) remains a leading cause of morbidity and mortality after heart transplantation. Annual screening is recommended to improve risk stratification and early treatment of CAV and is often performed with invasive coronary angiography (ICA). Coronary computed tomography angiography (CCTA) with CCTA-derived fractional flow reserve (FFRct) might be a non-invasive alternative to ICA for the surveillance of CAV providing both anatomical and functional information.
Purpose
To describe our initial results with CCTA and FFRct for detection of CAV in a cohort of heart transplant patients.
Methods
Heart transplant patients who underwent CCTA with FFRct as part of routine annual assessment for CAV were enrolled in a prospective registry from February 2018 to February 2019 in a single center. The most recently known CAV score (0–3) based on invasive angio and single photon emission computed tomography (SPECT) before CCTA was recorded. CCTA image quality was scored as non-diagnostic, moderate, good or excellent. FFRct analysis was performed off-site by a commercial company. For each coronary stenosis >30%, an FFRCTvalue distal to the stenosis was measured. For the RCA, LAD and CX without a stenosis, the FFRct value in the most distal location in the vessel was recorded. CAV classification was rescored based on CCTA. Demographics, additional diagnostic tests, and treatment plans were evaluated including major adverse events (MACE) during 90-day follow-up.
Results
65 patients (56 (39–65) years (median/ 25th–75thpercentile), 40% women) that were 11 (7–16) years after transplantation were included. The most recent CAV score was 0 in 52 patients (80%) and 1 or 2 in 13 patients. CCTA image quality was good or excellent in 59 (91%) patients. CCTA reclassified CAV scores in 32 (49%) patients to 33 patients with CAV 0, 18 patients with CAV 1, 9 patients with CAV 2 and 5 patients with CAV 3. In 17 patients (26%) at least one stenosis with FFRct ≤0.80 was detected including 11 patients with single vessel disease, 5 with two-vessel disease and one with three-vessel disease. In the 48 patients without a focal stenosis, mean distal FFRct values were 0.88 (0.86–0.91), 0.87 (0.85–0.90) and 0.90 (0.86–0.91) at less than 10, 10–15 or more than 15 years after transplantation, respectively (p=0.457). Additional tests were performed in 10 (15%) patients (1 SPECT and 10 invasive coronary angiographies), which resulted in revascularization by PCI in 6 (9%) patients. No MACE occurred during 90-day follow-up.
Conclusion
CCTA with FFRct can be successfully performed in heart transplant patients, detects patients with significant coronary stenosis and CCTA leads to substantial reclassification of CAV grades.
Acknowledgement/Funding
FFRct analysis was performed as part of the ADVANCE registry which is supported by Heartflow Inc.
Coronary Stenosis Detection by 16-Slice Computed Tomography in Heart Transplant Patients
